Abstract: A fuel cell includes an anode layer, a polymeric ion conductive membrane disposed over the anode layer, a cathode layer disposed over the polymeric ion conductive membrane, and an effective amount of a reactive material that corrodes at a higher rate than support carbon in the cathode layer, anode layer, or both. The reactive material is either proximate to or distributed within the cathode catalyst layer. In a variation, reactive material is also included proximate to the anode layer.

Abstract: A membrane humidifier for a fuel cell is disclosed, wherein a pressure drop in the humidifier is minimized and a humidification of a proton exchange membrane in the fuel cell is optimized.

Abstract: A process comprising: providing a substrate with a catalyst layer thereon; depositing a first ionomer overcoat layer over the catalyst layer, the first ionomer overcoat layer comprising an ionomer and a first solvent; drying the first ionomer overcoat layer to provide a first electrode ionomer overcoat layer; depositing a second ionomer overcoat layer over the first electrode ionomer overcoat layer, and wherein the second ionomer overcoat layer comprises an ionomer and a second solvent.

Abstract: A process comprising: depositing a liquid bonding layer comprising an ionomer and a solvent over a carrier film; placing a decal substrate over the liquid bonding layer and drying the liquid bonding layer to provide a solid bonding layer comprising the ionomer, and the solid bonding layer bonding the decal substrate and carrier film together.

Abstract: A fuel cell including an anode-side catalyst coated diffusion medium and a cathode-side catalyst coated diffusion medium that sandwich an ionically conductive membrane. A sealing material is disposed between the ionically conductive membrane and the anode-side and cathode-side catalyst coated diffusion medium, wherein the sealing material is formed of a material that has a permeability that is less than a permeability of the ionically conductive member. The sealing material may also be formed of a material that is softer than the ionically conductive membrane such that the sealing material may deform and enable an membrane electrode assembly of the fuel cell to be subjected to uniform pressures throughout the assembly.

Abstract: A method of manufacturing a fuel cell membrane electrode assembly comprising forming and compressing a stack having a plurality of layers in a desired orientation. The layers comprise a membrane, a cathode, an anode, and at least one edge protection layer. The method includes providing at least one mechanical reinforcing layer adjacent the anode or cathode layer, and allowing the electrodes to relax under high heat to remove stress prior to lamination.

Abstract: Fuel cells are provided that are at least partially resistant to corrosion, including the use of components that are comprised of materials that are at least partially resistant to corrosion. The fuel cells include subgasket materials and designs, involving geometric arrangements of the subgasket that reduce oxygen permeation from, the cathode to the anode side of the membranes and/or hydrogen permeation from the anode to the cathode side of the membranes. In addition to using protonically non-conductive subgasket materials with lower oxygen and/or hydrogen permeabilities, versus ionomeric subgaskets which are protonically conducting and have high O2 permeation rates, the elimination of the microporous layer (e.g., coated onto the diffusion medium) directly beneath the permeable subgasket materials will also reduce production of corrosive species. The elimination of direct contact between the bipolar plate material surface and PFSA ionomer membrane material also prevents corrosion to the metal bipolar plates.

Abstract: A fuel cell electrocatalyst layer having increased voltage cycling durability. The electrocatalyst layer comprises annealed platinum particles having an average particle size diameter from about 3 to about 15 nm deposited on a support structure. The platinum particles are annealed at a temperature from about 800 to about 1,400° C. for a time period such that the surface area is reduced by about 20% as compared to the original surface area. In various embodiments, the electrocatalyst layer retains an electrochemical surface area that is greater than 50% of an original electrochemical surface area after about 15,000 voltage cycles in the range from about 0.6 to about 1.0 V.

Abstract: A gradient of ionomeric material is generated, disposed, or otherwise provided in an electrode suitable for use in a fuel cell. The ionomer concentration, e.g., with respect to the carbon content of the catalyst layer (e.g., expressed as a ratio), is greatest in the area closest to the membrane, e.g., of the fuel cell (e.g., the membrane side), and is decreased in the area furthest from the membrane (e.g., the gas side). By way of another non-limiting example, the ionomer gradient can be formed such that the concentration (or the ratio if expressed in relation to the carbon content of the catalyst layer) can gradually, as opposed to rapidly, decrease as the distance away from the membrane increases.

Abstract: A gas diffusion medium with microporoous bilayer is disclosed. The gas diffusion medium includes a diffusion medium substrate, with a dual layer, including a first sublayer that is comprised of a variation in particle sizes and second layer composed of one material with a uniform particle size. The gas diffusion medium with microporous bilayer has enhanced cushioning and water management properties.

Abstract: A fuel cell including an anode-side catalyst coated membrane and a cathode-side catalyst coated membrane. At least a portion of a reduced-permeability layer is disposed between the ionically conductive membrane and the anode-side and cathode-side gas diffusion media, wherein the reduced-permeability layer is formed of a material that has a permeability that is less than a permeability of the ionically conductive member. The reduced-permeability layer may also be formed of a material that is softer than-the ionically conductive membrane.

Abstract: A membrane electrode assembly comprising an ionically conductive member and an electrode, wherein the electrode is a smooth, continuous layer that completely covers and supports the ionically conductive member. The electrode further comprises a central region and a peripheral region, wherein a gradient of electrochemically active material exists between the central region and the peripheral region such that a content of the electrochemically active material is greater in the central region than the peripheral region.

Abstract: A membrane electrode assembly comprising an ionically conductive member and an electrode, wherein the electrode is a smooth, continuous layer that completely covers and supports the ionically conductive member. The electrode further comprises a central region and a peripheral region, wherein a gradient of electrochemically active material exists between the central region and the peripheral region such that a content of the electrochemically active material is greater in the central region than the peripheral region.

Abstract: A hydrogen fuel cell stack has at least two segments of fuel cells each having reactant gas passages. The reactant gas passages of each fuel cell in each segment are arranged in parallel with each other. Flow of fuel cell fluids is in a gravity assisted downward direction. Gravity assisted flow directs water formed in each cell to lower removal points of the stack segments. Adjacent segments are separated by either a separator segment formed as an integral unit with the stack or the segments are joined and an external piping system directs flow to differing stack areas. A cathode flow enters at a first stack end and a hydrogen anode flow enters the stack at an opposite end, such that cathode and anode flows are counter-current to each other. A coolant flow is normally injected adjacent to and flows parallel with the cathode flow, but can also be directed by the piping system to any or all segments in series or parallel.

Abstract: A low humidification and durable fuel cell membrane is provided with water adsorbing material embedded therein in order to adsorb water under wet conditions and provide a reservoir of water to keep the membrane irrigated under dry conditions. A hydrogen oxidation catalyst is provided on the water adsorbing material which will catalyze the reaction of hydrogen and oxygen that are crossing through the membrane and will serve to irrigate the membrane and keep the water adsorbing material full of water. Accordingly, the humidification requirements to a fuel cell stack in an operating system are reduced.

Abstract: A fuel cell comprising an ionically conductive membrane with an electrode. The electrode is disposed adjacent the ionically conductive membrane and an electrically conductive member is disposed adjacent the electrode. The fuel cell further comprises a group of catalyzed particles that is capable of catalyzing a gas phase oxidation reaction and an electrochemical oxidation reaction. The catalyzed particles are disposed on at least one of the electrode and electrically conductive member.

Abstract: A fuel cell stack has at least two segments of fuel cells each having reactant gas passages. Each of the cells in each segment is arranged such that the reactant gas passages of each cell are in parallel with each other cell. Flow of fuel cell fluids, normally in a gaseous state on the anode and cathode side of each cell, is in a gravity assisted downward direction. Gravity assisted flow directs water formed in each cell to lower removal points of the stack segments. Each pair of segments is separated by a separator segment having a separator channel, the separator segment forming an integral unit of the stack. Each separator channel redirects the entire flow of each fluid within the stack from the bottom of an upstream segment to the top of a next or downstream segment, without reacting the fluid, controlling relative humidity between stack segments.

Abstract: In one aspect a substrate such as a sheet metal product, in particular for use as a bipolar plate in a fuel cell or in an electrolyzer, is characterized in that it has, on at least one side, a conductive and corrosion-resistant protective coating of a metal oxide having a treatment which ensures the conductivity. The coating can be produced by introducing a piece of sheet metal into a coating plant and providing it with the conductive and corrosion-resistant protective coating of the metal oxide. In another aspect, an electrochemical cell such as a fuel cell comprises an electrically conductive contact element having a first surface facing an electrode for conducting electrical current, and the contact element comprises an electrically conductive substrate and an electrically conductive coating comprising a doped metal oxide, desirably a doped tin oxide, and preferably a fluorine doped tin oxide.

Abstract: A membrane electrode assembly comprising an ionically conductive member and an electrode, wherein the electrode is a smooth, continuous layer that completely covers and supports the ionically conductive member. The electrode further comprises a central region and a peripheral region, wherein a gradient of electrochemically active material exists between the central region and the peripheral region such that a content of the electrochemically active material is greater in the central region than the peripheral region.

Abstract: A fuel cell stack has at least two segments of fuel cells each having reactant gas passages. Each of the cells in each segment is arranged such that the reactant gas passages of each cell are in parallel with each other cell. Flow of fuel cell fluids, normally in a gaseous state on the anode and cathode side of each cell, is in a gravity assisted downward direction. Gravity assisted flow directs water formed in each cell to lower removal points of the stack segments. Each pair of segments is separated by a separator segment having a separator channel, the separator segment forming an integral unit of the stack. Each separator channel redirects the entire flow of each fluid within the stack from the bottom of an upstream segment to the top of a next or downstream segment, without reacting the fluid, controlling relative humidity between stack segments.